Dosing and uses of Krystexxa (pegloticase)
Adult dosage forms and strengths
injectable solution
- 8mg/mL
Gout
Indicated for treatment of chronic gout in adult patients refractory to conventional treatment
8 mg IV infusion q2wk (see Administration)
Pediatric dosage forms and strengths
<18 years: Safety and efficacy not established
Krystexxa (pegloticase) adverse (side) effects
>10%
Gout flares (77%)
Infusion reactions (26%)
Nausea (12%)
Urticaria (10.6%)
1-10%
Chest discomfort (9.5%)
Chest pain (9.5%)
Erythema (9.5%)
Pruritus (9.5%)
Nasopharyngitis (7%)
Anaphylaxis (5%)
Postmarketing Reports
Hemolysis and methemoglobinemia in patients with G6PD deficiency
Warnings
Black box warnings
Anaphylaxis and infusion reactions have been reported; these reactions may occur with any infusion, including the first, and typically manifest within 2 h of infusion (although delayed-type hypersensitivity has also been reported)
Only administer in a healthcare setting, and monitor for appropriate period following infusion
Premedicate with antihistamines and corticosteroids
Risk for anaphylaxis is higher if serum uric acid level >6 mg/dL, monitor serum uric acid levels before infusion and consider discontinuing if levels increase to >6 mg/dL (particularly if 2 consecutive levels of >6 mg/dL are observed)
Do not administer to patients with history of G6PD Deficiency; Screen patients at risk for G6PD Deficiency prior to initiating therapy; Life threatening hemolytic reactions and methemoglobinemia have been reported in these patients
Contraindications
Hypersensitivity
G6PD-deficiency (increased risk of hemolysis and methemoglobinemia)
Cautions
Gout flare frequently observed (initiate gout flare prophylaxis with NSAID or colchicine at least 1 wk before starting pegloticase); gout flare prophylaxis recommended for at least first 6 months
Screen patients at higher risk of G6PD deficiency, especially those of African and Mediterranean ancestry
Caution with congestive heart failure (not formally studied in patients with CHF); congestive heart failure exacerbation may occur; monitor patients closely following infusion
Unknown if retreatment after stopping for longer than 4 wk increases risk of anaphylaxis, infusion reactions, or immunogenicity
Risk of infusion reaction is increased in patients whose uric acid is >6 mg/dL; if less than severe infusion reactions occur, may slow infusion or infusion stopped and restarted at lower rate at physician's discretion
Discontinue use of oral antihyperuricemic agents prior to therapy; do not initiate during course of therapy; agents may delay interpretation of ineffective pegloticase treatment
Patients may be at increased risk for anaphylaxis and infusion reactions, when treatment is discontinued for >4 weeks, due to potential to immunogenicity
Administered by IV infusion over no less than 120 min via gravity feed, syringe-type pump, or infusion pump
Pre-medicate patients with antihistamines and corticosteroids before treating
Monitor serum uric acid levels before each infusion
Pregnancy and lactation
Pregnancy category: C
Lactation: Unknown whether distributed in breast milk; if it is distributed into breast milk, the potential for serious adverse reactions exist, therefore breastfeeding is not recommended
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Krystexxa (pegloticase)
Mechanism of action
Recombinant, pegylated uric acid specific enzyme; achieves its therapeutic effect by catalyzing oxidation of uric acid to allantoin, thereby lowering serum uric acid levels
Pharmacokinetics
Onset of action: 24 hr
Duration: 12.5 days
Half-life: 14 days
Administration
IV Compatibilities
Solution: 0.9% NaCl, 0.45% NaCL
IV Preparation
IV infusion
- Withdraw 1 mL from vial (discard any unused portion) and add to a single 250 mL bag of 0.9% or 0.45% NaCl
- Invert infusion bag a number of times to ensure thorough mixing
- DO NOT SHAKE
- Stability: Admixture is stable for 4 hr at 2-8 degrees C (36-46 degrees F) or at room temperature (20-25 degrees C, 68-77 degrees F)
IV Administration
Do NOT administer as IV push or bolus
Premedicate with antihistamines and corticosteroids
Monitor serum uric acid levels prior to infusions and consider discontinuing treatment if levels increase to >6 mg/dL (especially if 2 consecutive levels > 6 mg/dL observed)
Administer IV infusion over at least 2 hr via gravity feed or volumetric infusion pump
Storage
Store refrigerated in original carton (do not freeze)
Protect from light
Do not shake
